U.S. patent number 7,003,888 [Application Number 10/414,265] was granted by the patent office on 2006-02-28 for clamping arrangement for receiving a saw blade.
This patent grant is currently assigned to Black & Decker Inc.. Invention is credited to Jonathan D. C. Bigden, Stephen C. Dassoulas, James J. Derreth, Jeffrey P. Grant, Jason R. Melvin, Robert G. Moores, Jr..
United States Patent |
7,003,888 |
Bigden , et al. |
February 28, 2006 |
Clamping arrangement for receiving a saw blade
Abstract
A saw blade clamping arrangement for a power tool includes a
clamp support, a biasing member and an actuation member. The clamp
support is interconnected with the drive shaft for reciprocating
motion with the drive shaft relative to a housing of the power
tool. The clamp support is configured to selectively receive a saw
blade of the power tool in various orientations. A release lever is
carried by the housing and is manually rotated to move a control
member between a first position in which the saw blade is coupled
to the drive shaft and a second position in which the saw blade may
be displaced from the drive shaft. In at least one of the
orientations, the saw blade is positioned offset from the drive
shaft and proximate one of the side walls of the tool housing to
allow for flush cutting of a work piece.
Inventors: |
Bigden; Jonathan D. C.
(Baltimore, MD), Dassoulas; Stephen C. (Baltimore, MD),
Melvin; Jason R. (Towson, MD), Moores, Jr.; Robert G.
(Reistertown, MD), Grant; Jeffrey P. (Forest Hill, MD),
Derreth; James J. (Baltimore, MD) |
Assignee: |
Black & Decker Inc.
(Newark, DE)
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Family
ID: |
32507435 |
Appl.
No.: |
10/414,265 |
Filed: |
April 15, 2003 |
Prior Publication Data
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Document
Identifier |
Publication Date |
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US 20040068876 A1 |
Apr 15, 2004 |
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Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
Issue Date |
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10337232 |
Jan 6, 2003 |
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09955374 |
Sep 17, 2001 |
6502317 |
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09416819 |
Oct 12, 1999 |
6295736 |
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09057788 |
Apr 9, 1998 |
6023848 |
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08881091 |
Jun 24, 1997 |
6009627 |
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08744023 |
Nov 5, 1996 |
5794352 |
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08504050 |
Jun 9, 1995 |
5647133 |
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Current U.S.
Class: |
30/392;
279/79 |
Current CPC
Class: |
B23D
49/167 (20130101); B23D 51/10 (20130101); Y10T
279/29 (20150115); Y10T 279/22 (20150115); Y10T
279/17786 (20150115) |
Current International
Class: |
B23D
61/12 (20060101); B27B 19/00 (20060101) |
Field of
Search: |
;30/392-394,338
;279/79 |
References Cited
[Referenced By]
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230 2060 |
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198 19 527 |
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DE |
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198 19 530 |
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Nov 1999 |
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DE |
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199 47 840 |
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199 51 040 |
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200 13 789 |
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WO 02/32607 |
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Apr 2002 |
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WO |
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Primary Examiner: Watts; Douglas D
Attorney, Agent or Firm: Harness, Dickey & Pierce,
P.L.C.
Parent Case Text
CROSS-REFERENCE TO RELATED APPLICATIONS
This is a continuation of U.S. Ser. No. 10/337,232, filed Jan. 6,
2003, which is a continuation-in-part application of U.S. Ser. No.
09/955,374, filed Sep. 17, 2001 (now U.S. Pat. No. 6,502,317),
which is a continuation of U.S. Ser. No. 09/416,819, filed Oct. 12,
1999 (now U.S. Pat. No. 6,295,736), which is a continuation-in-part
application of U.S. Ser. No. 09/057,788 filed Apr. 9, 1998 (now
U.S. Pat. No. 6,023,848), which is a continuation-in-part
application of U.S. Ser. No. 08/881,091 filed Jun. 24, 1997 (now
U.S. Pat. No. 6,009,627), which is a continuation-in-part
application of U.S. Ser. No. 08/744,023 filed Nov. 5, 1996 (now
U.S. Pat. No. 5,794,352), which is a continuation-in-part
application of U.S. Ser. No. 08/504,050, filed Jun. 9, 1995 (now
U.S. Pat. No. 5,647,133).
Claims
What is claimed is:
1. A saw blade clamping arrangement for a power tool including a
housing, a drive shaft mounted for longitudinal reciprocating
motion relative to the housing along an axis, and a saw blade
releasably interconnected with the drive shaft, the saw blade
clamping arrangement comprising: a support member for attachment to
the drive shaft; a control member carried by the support member,
the control member movable in a direction substantially
perpendicular to the axis between a first position and a second
position; a locking member operative for selectively engaging the
saw blade with the drive shaft such that the saw blade and the
drive shaft are operatively engaged when the control member is in
the first position and the saw blade and the drive shaft are
permitted to be operatively disengaged when the control member is
in the second position; and an actuation member for attachment to
the housing, the actuation member operative to move the control
member from the first position to the second position.
2. The saw blade clamping arrangement for a power tool of claim 1,
wherein the actuation member is fixed with respect to the housing
in a direction parallel to the axis.
3. The saw blade clamping arrangement for a power tool of claim 2,
wherein the actuation member is movable between a clamping position
in which the control member is in the first position for urging the
locking member into operative engagement with the saw blade and a
release position in which the actuation member directly engages the
control member and the control member is moved to the second
position for permitting displacement of the locking member from the
saw blade.
4. The saw blade clamping arrangement for a power tool of claim 1,
wherein the locking member is at least partially disposed in an
aperture defined by the support member and movable within the
aperture in a direction substantially perpendicular to the
axis.
5. The saw blade clamping arrangement for a power tool of claim 1,
wherein the locking member comprises at least one locking ball.
6. The saw blade clamping arrangement for a power tool of claim 1,
wherein the control member defines a cam surface for urging the
locking member into engagement with the saw blade as the control
member is moved from the first position to the second position.
7. The saw blade clamping arrangement for a power tool of claim 1,
further comprising a biasing member for biasing the control member
to the first position.
8. The saw blade clamping arrangement for a power tool of claim 7,
wherein the biasing member comprises a coil spring surrounding the
support member, the coil spring including a first end engaging the
support member and a second end engaging the control member.
9. The saw blade clamping arrangement for a power tool of claim 1,
wherein the control member is linearly movable in the direction
substantially perpendicular to the axis.
10. The saw blade clamping arrangement for a power tool of claim 1,
wherein the actuation member directly engages the control member to
move the control member from the first position to the second
position.
11. The saw blade clamping arrangement for a power tool of claim 1
in combination with the power tool.
12. The saw blade clamping arrangement for a power tool of claim
11, wherein the power tool is a reciprocating saw.
13. A saw blade clamping arrangement for a power tool including a
housing, a drive shaft mounted for longitudinal reciprocating
motion relative to the housing along an axis, and a saw blade
releasably interconnected with the drive shaft, the saw blade
clamping arrangement comprising: a support member for attachment to
the drive shaft; a control member carried by the support member,
the control member defining a camming surface and being movable
between a first position and a second position; a locking member
operative for selectively engaging the saw blade with the drive
shaft such that the saw blade and the drive shaft are operatively
engaged when the control member is in the first position and the
saw blade and the drive shaft are permitted to be operatively
disengaged when the control member is in the second position; and
an actuation member for attachment to the housing, the actuation
member operative to move the control member from the first position
to the second position.
14. The saw blade clamping arrangement for a power tool of claim
13, wherein the control member is movable in a direction
substantially perpendicular to the axis between a first position
and a second position.
15. The saw blade clamping arrangement for a power tool of claim
13, wherein the actuation member is fixed with respect to the
housing in a direction parallel to the axis.
16. The saw blade clamping arrangement for a power tool of claim
13, wherein the actuation member is movable between a clamping
position in which the control member is in the first position for
urging the locking member into operative engagement with the saw
blade and a release position in which the actuation member directly
engages the control member and the control member is moved to the
second position for permitting displacement of the locking member
from the saw blade.
17. The saw blade damping arrangement for a power tool of claim 13,
wherein the locking member is at least partially disposed in an
aperture defined by the support member and movable within the
aperture in a direction substantially perpendicular to the
axis.
18. The saw blade clamping arrangement for a power tool of claim
13, wherein the locking member comprises at least one locking ball
that cooperates with the camming surface.
19. The saw blade clamping arrangement for a power tool of claim
13, further comprising a biasing member for biasing the control
member to the first position.
20. The saw blade clamping arrangement for a power tool of claim
19, wherein the biasing member comprises a coil spring surrounding
the support member, the coil spring including a first end engaging
the support member and a second end engaging the control
member.
21. The saw blade clamping arrangement for a power tool of claim
14, wherein the control member is linearly movable in the
direction.
22. The saw blade clamping arrangement for a power tool of claim
13, wherein the actuation member directly engages the control
member to move the control member from the first position to the
second position.
23. The saw blade clamping arrangement for a power tool of claim 13
in combination with the power tool.
24. The saw blade clamping arrangement for a power tool of claim
23, wherein the power tool is a reciprocating saw.
Description
FIELD OF THE INVENTION
The present invention relates in general to power tools. In
particular, the present invention relates to saw blade clamping
arrangements for power tools having a saw blade mounted to a shaft
for reciprocating cutting motion.
BACKGROUND OF THE INVENTION
Power reciprocating saws including jigsaws and other reciprocating
saws are generally referred to in the trade as "recip" saws. These
saws incorporate reciprocating drive shafts. The drive shafts
operate to drive generally linear saw blades along a predetermined
path so as to provide one of a rectilinear or orbital cutting
action.
In a conventional manner, the saw blades used with such power tools
are attached to the reciprocating drive shafts through a blade
holder having a slot for receiving the saw blade and a set screw
which is received in a hole in the blade. The blade is clamped in
place relative to the reciprocating drive shaft through tightening
of the set screw. While this conventional manner of saw blade
attachment has proven to be generally satisfactory and commercially
successful, it is not without inherent disadvantages. For example,
power reciprocating saws are subject to high vibration forces
during operation which frequently result in loosening of the set
screw. If the set screw does not remain sufficiently tightened, the
saw blade may become disengaged from the drive shaft. An additional
disadvantage with the conventional mounting of saw blades to
reciprocating drive shafts relates to an inability to quickly and
easily remove saw blades which become worn or fractured. Because it
is often desirable to cut a work piece with minimum material loss,
it is desirable to correspondingly minimize the saw blade
thickness. As a result, breakage due to the forces encountered
during typical use is not an uncommon occurrence. This potential
frequency of blade changing makes the ease and rapidity of such
action desirable. A further disadvantage of conventional blade
clamping arrangements is the necessity for a separate tool such as
a wrench for fixation and removal of the saw blade.
Many previous attempts have been made to overcome the disadvantages
associated with the above-described conventional mounting of saw
blades through elimination of the use of a set screw. However, all
of these previous attempts are subject to further refinement and
improvement. For example, most of the known devices are complicated
and expensive to manufacture and assemble as a result of a
construction including many separate parts. Additionally, operation
of many of the prior devices requires application of force which is
often significant for securing the saw blade in place and loosening
of the blade for separation from the drive shaft. Achieving a
sufficient force often requires the use of a wrench or other
tool.
Conventional saw blade clamping arrangements also generally suffer
from an inability to receive a saw blade in multiple orientations.
To the limited extend that conventional saw blade clamping
arrangements are able to receive the saw blade in multiple
orientations, such arrangements are not able to cooperate with a
release lever carried by a housing of the tool. Additionally, such
arrangements typically require complicated mechanisms for
alternatively securing the saw blade to the drive shaft in the
various orientations.
It remains a need in the pertinent art to provide a saw blade
clamping arrangement for a reciprocating saw that overcomes the
above and other disadvantages associated with the prior art. In a
similar regard, it remains a continuous goal of the pertinent art
to improve cutting flexibility of reciprocating saws to avoid
obstacles while retaining cutting efficiencies and quality.
SUMMARY OF THE INVENTION
The present invention provides various embodiments to saw blade
clamping arrangements for reciprocating power tools that overcome
disadvantages associated with the prior art. More particularly, the
present invention provides a new and improved saw blade clamping
arrangement for a power reciprocating saw which includes a release
lever operative to permit quick and easy installation and removal
of a saw blade. The present invention also provides a new and
improved saw blade clamping arrangement for a power reciprocating
saw that is operative to receive the saw blade in multiple
orientations.
In the preferred embodiments of the present invention to be
described in detail below, the release lever is pivotally mounted
for movement between two positions. Further in the preferred
embodiments, the release lever is not interconnected with the drive
shaft for reciprocating movement therewith. Rather, the release
lever is pivotally attached to the housing, thereby reducing the
mass carried by the reciprocating shaft.
Advantageously, the present invention provides a saw blade clamping
arrangement for a power reciprocating saw of simple construction
which is relatively inexpensive to manufacture and assemble.
Additionally, the present invention provides a blade clamping
arrangement which can accommodate conventional saw blades of
various constructions and which can hold the saw blade in place
without the use of set screws and without the need to employ any
other form of a tool. Still yet, the present invention provides a
blade clamping arrangement having a design which protects its
components from excessive wear and premature failure. According to
one particular feature, the present invention also provides a saw
blade clamping arrangement operative to receive a saw blade in
multiple orientations to improve flexibility of the tool to avoid
obstacles.
In one particular form, the present invention provides a saw blade
clamping arrangement for a power tool including a housing, a drive
shaft mounted for reciprocating motion relative to the housing, and
a saw blade releasably interconnected with the drive shaft. The
clamping arrangement includes a clamp body or clamp support carried
by the drive shaft operative to receive the saw blade in at least
mutually perpendicular two orientations. The saw blade clamping
arrangement further includes a slider or control member connected
to the clamp support for movement between a first position and a
second position. The control member includes a first portion for
selectively creating an operative connection between the saw blade
and the drive shaft when the saw blade is received by the clamp
support in a first of the at least two mutually perpendicular
orientations. The control member further includes a second portion
for selectively creating an operative connection between the saw
blade and the drive shaft when the saw blade is received by the
clamp support in a second of the at least two mutually
perpendicular orientations.
In another particular form, the present invention similarly
provides a saw blade clamping arrangement for a power tool
including a housing, a drive shaft mounted for reciprocating motion
relative to the housing, and a saw blade releasably interconnected
with the drive shaft for reciprocating motion along a longitudinal
axis. In this particular form the saw bade clamping arrangement
includes a clamp support for attachment to the drive shaft that
defines a vertical slot for receiving the saw blade in a vertical
orientation. The clamp support further defines a horizontal slot
for receiving the saw blade in a horizontal orientation. The
vertical slot is spaced from the horizontal slot.
In yet another particular form, the present invention again
provides a saw blade clamping arrangement for a power tool
including a housing, a drive shaft mounted for reciprocating motion
relative to the housing, and a saw blade releasably interconnected
with the drive shaft for reciprocating motion along a longitudinal
axis. The saw blade clamping arrangement includes a clamp support,
a control member and a release lever. The clamp support is
interconnected with the drive shaft and is configured to
selectively receive the saw blade in at least two orientations. The
control member is connected to the clamp support and creates an
operative connection between the saw blade and the drive shaft when
the saw blade is received by the clamp support in any of the at
least two orientations. The control member is movable between a
first position for creating the operative connection and a second
position permitting removal of the saw blade. The release lever is
mounted to the housing and is normally spaced from the control
member. The release lever is manually movable to engage the control
member and displace the control member from the first position to
the second position.
BRIEF DESCRIPTION OF THE DRAWINGS
Additional objects and advantages of the present invention will
become apparent from a reading of the following detailed
description of the preferred embodiments which makes reference to
the drawings of which:
FIG. 1 is a side elevational view of a reciprocating saw
incorporating a saw blade clamping arrangement constructed in
accordance with the teachings of a first preferred embodiment of
the present invention.
FIG. 2 is an exploded perspective view of the saw blade clamping
arrangement of the present invention.
FIG. 3 is an enlarged side view of the clamp support member shown
in FIG. 2.
FIG. 4 is an enlarged end view of the clamp support member.
FIG. 5 is an enlarged side view of the clamp spring member shown in
FIG. 2.
FIG. 6 is an enlarged end view of the clamp spring member.
FIG. 7 is a partial side view of the saw blade clamping arrangement
of FIG. 1, illustrating interconnection of the drive shaft with a
conventional saw blade.
FIG. 8 is a partial cross-sectional view of the keyless saw blade
clamp of FIG. 1 taken along the line 8--8 of FIG. 1 illustrated
with the end plate of FIG. 2 removed for purposes of clarity.
FIG. 9 is a partial view of a mounting portion of a first
alternative saw blade configuration acceptable for use with the saw
blade clamping arrangement of the present invention.
FIG. 10 is a partial view of a mounting portion of a second
alternative saw blade configuration acceptable for use with the
keyless saw blade clamping arrangement of the present
invention.
FIG. 11 is a cross-sectional view of the clamping assembly of FIG.
1 taken along the line 11--11 of FIG. 1, illustrating the release
lever rotated to a first stable position in which the clamp spring
member of the clamping assembly biases the saw blade into operative
connection with the drive shaft.
FIG. 12 is a cross-sectional view similar to that shown in FIG. 11,
illustrating the release lever in a second stable position in which
the clamp spring member is displaced from the saw blade by the
release lever, thereby permitting the saw blade to be easily
removed from the clamp assembly.
FIG. 13 is an exploded view of a saw blade clamping arrangement
constructed in accordance with the teachings of a second preferred
embodiment of the present invention and a portion of a
reciprocating saw.
FIG. 14 is an enlarged side view of the clamp support member of the
second preferred embodiment shown in FIG. 13.
FIG. 15 is a cross-sectional view taken along the line 15--15 of
FIG. 14.
FIG. 16 is an enlarged side view of the locking pin member of the
second embodiment shown in FIG. 13.
FIG. 17 is an enlarged side view of the spring clamp member of the
second embodiment shown in FIG. 13.
FIG. 18 is a partial cross-sectional view of the saw blade clamping
arrangement of FIG. 13, illustrating the lever rotated to a first
position in which the locking pin member is displaced from the slot
which receives the saw blade, thereby permitting the saw blade to
be easily removed or inserted from the clamp support member.
FIG. 19 is a partial cross-sectional view similar to that shown in
FIG. 18, illustrating the release lever in a second position in
which the clamp spring member biases the locking pin member into a
locked position for retaining the saw blade within the slot.
FIG. 20 is a side view of a portion of a reciprocating saw
illustrated to include a partial cross-sectional view of a saw
blade clamping arrangement constructed in accordance with the
teachings of a third preferred embodiment of the present
invention.
FIG. 21 is an end view of the reciprocating saw of FIG. 20,
illustrating the saw blade clamping arrangement in a clamped
position.
FIG. 22 is an end view similar to FIG. 21, illustrating the saw
blade clamping arrangement in a release position.
FIG. 23 is an enlarged side view of the saw blade clamping
arrangement of FIG. 20 shown removed from the reciprocating saw for
purposes of illustration.
FIG. 24 is an end view of the saw blade clamping arrangement of
FIG. 22.
FIG. 25 is a top view of the clamp support member of FIG. 24.
FIG. 26 is a top view of the clamp support member of FIG. 24.
FIG. 27 is a side view of the slider member of FIG. 24.
FIG. 28 is a cross-sectional view taken along the line 28--28 of
FIG. 27.
FIG. 29 is an end view of the collar of FIG. 24.
FIG. 30 is a side view of the collar of FIG. 24.
FIG. 31 is a cross-sectional view taken along the line 31--31 of
FIG. 30.
FIG. 32A is a perspective view of a first end of an outer member of
an alternative collar for use with saw blade clamping arrangement
of the third preferred embodiment of the present invention.
FIG. 32B is a perspective view of a second end of the outer
member.
FIG. 33A is a perspective view of a first end of an inner member
intended to cooperate with the outer member of FIG. 30.
FIG. 33B is a perspective view of a second end of the inner
member.
FIG. 34 is a view similar to FIG. 26, enlarged and illustrating the
saw blade held in position within the clamp by the bearing and the
locating pin.
FIG. 35 is a partially cut-away view of a saw blade clamping
arrangement constructed in accordance with the teachings of a
fourth preferred embodiment of the present invention shown to
include a saw blade ejection mechanism, the saw blade ejection
mechanism shown in a retracted state.
FIG. 36 is a partially cut-away view similar to FIG. 35,
illustrating the saw blade ejection mechanism in an extended
state.
FIG. 37 is a cross-sectional view taken along the line 37--37 of
FIG. 26.
FIG. 38 is a side view of the plunger of the fourth preferred
embodiment of the present invention shown removed from the
environment of FIGS. 35 and 36 for purposes of illustration.
FIG. 39 is a side view of the cap of the fourth preferred
embodiment of the present invention shown removed from the
environment of FIGS. 35 and 36 for purposes of illustration.
FIG. 40 is a cross-sectional view taken along the line 40--40 of
FIG. 39.
FIG. 41 is a perspective view of a reciprocating saw incorporating
a saw blade clamping arrangement constructed in accordance with the
teachings of a fifth preferred embodiment of the present invention,
the saw blade clamping arrangement shown operatively associated
with a saw blade in a first orientation.
FIG. 42 is a perspective view illustrating a portion of the
reciprocating saw of FIG. 41, the saw blade clamping arrangement
shown operatively associated with the saw blade in a second
orientation.
FIGS. 43A and 43B are a perspective view similar to FIG. 42 with
the saw blade clamping arrangement shown operatively associated
with the saw blade in a third orientation and a side view of the
saw blade clamping arrangement securing the saw blade in the third
orientation to a drive shaft of the tool, respectively.
FIG. 44 is a perspective view similar to FIG. 42, the saw blade
clamping arrangement shown operatively associated with the saw
blade in a fourth orientation.
FIGS. 45A-45C are various views of a clamp base of the saw blade
clamping arrangement of FIGS. 41-44.
FIGS. 46A-46C are various views of a slider of the saw blade
clamping arrangement of FIGS. 41-44.
FIG. 47 is a cross-sectional view taken along the line 47--47 of
FIG. 41.
FIG. 48 is a cross-sectional view similar to FIG. 47, illustrating
the lever articulated to a blade release position.
FIG. 49 is a cross-sectional view taken along the line 49--49 of
FIG. 41.
FIG. 50 is a perspective view of the reciprocating saw of FIG. 41,
illustrating the saw blade in the third position and the
reciprocating saw being used for flush-cutting of a work piece.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
The present invention provides an improved saw blade clamping
arrangement for a power tool. While shown throughout the drawings
in various embodiments for a saw blade clamping arrangement
specifically adapted for a reciprocating saw, those skilled in the
art will appreciate that the invention is not so limited in scope.
In this regard, the various teachings of the present invention will
be understood to be readily adaptable for use with any power tool
incorporating one or more reciprocating cutting members (e.g.,
reciprocating saws, jig saws, various surgical saws and culinary
knives, etc.).
Turning generally to the drawings in which identical or equivalent
elements have been denoted with like reference numerals, and
specifically to FIGS. 1 through 12 thereof, a first preferred
embodiment of an exemplary power tool is shown. The exemplary power
tool embodies the teachings of the present invention and is
illustrated in FIG. 1 as a power reciprocating saw which has been
identified generally at reference numeral 10. In a conventional
manner, power reciprocating saw 10 is powered by a motor (not
shown) that is actuated by a trigger switch 12. The delivery of
electrical energy to the motor through a power cord (partially
shown at 14) is controlled by trigger switch 12.
In the exemplary embodiment illustrated, power tool 10 is shown to
include a handle portion 16 which carries trigger switch 12. Power
tool 10 is also shown to include a housing 18 that includes a
centrally located motor housing portion 20 and a forwardly located
gear case housing portion 22. As shown most clearly in FIG. 2, gear
case housing portion 22 is formed to include a front face 24 having
a generally rectangular aperture 26 which defines the opening of a
longitudinally extending drive shaft channel 28.
Power tool 10 further includes a drive shaft 30 partially extending
within drive shaft channel 28 and operatively connected with a
drive mechanism (not shown) housed within gear case housing portion
22. This interconnection between the drive mechanism and drive
shaft 30 can be in any manner well known in the art. Drive shaft 30
is mounted for reciprocating motion generally along the
longitudinal axis defined by power tool 10.
As shown in FIGS. 1 and 2, the housing 18 includes first and second
forwardly extending sidewall members 32 and 34 interconnected with
gear case housing portion 22. In the first preferred embodiment,
first and second forwardly extending side wall members 32 and 34
are integrally formed with gear case housing 22 and are constructed
of aluminum, magnesium or other suitable lightweight metal. The
particular configuration and function of first and second forwardly
extending sidewall members 32 and 34 will be described in detail
below.
Drive shaft 30 is adapted to cooperate with a cutting member such
as a saw blade 38 for driving the saw blade 38 back and forth in a
cutting motion along a rectilinear path. In this regard,
reciprocating drive shaft 30 is formed to include a transversely
extending aperture 40 for receiving a drive pin 42 (shown in FIG.
7). An interference fit retains drive pin 42 within aperture 40.
The saw blade construction shown in FIGS. 1 and 7 conventionally
includes a forwardly located cutting portion 44 integrally formed
with a rearwardly located mounting portion 46. In a manner well
known in the art, an aperture 48 formed in mounting portion 46 of
saw blade 38 receives drive pin 42 when saw blade 38 is mounted to
reciprocating drive shaft 30. The exposed end of drive pin 42
extends from a first side wall 52 (shown in FIG. 8) of
reciprocating shaft 30 in a dimension approximately equivalent to
the thickness of saw blade 38.
Power tool 10 of the present invention further includes a clamping
arrangement 56 for releasably maintaining saw blade 38 in operative
connection with reciprocating drive shaft 30. Clamping arrangement
56 is shown throughout the drawings to include a clamp support
member 58, a biasing member 60, and a actuation member 62. The
remainder of this detailed description of the first preferred
embodiment will be primarily directed to the construction and
operation of clamping arrangement 56 which is the focus of the
present invention.
Referring specifically to FIGS. 3 and 4, the construction and
operation of the clamp support member 58 will be described. In the
exemplary embodiment shown throughout the drawings, clamp support
member 58 is illustrated as a separate element which is adapted to
be interconnected with reciprocating drive shaft 30 for movement
therewith. However, it will be appreciated by those skilled in the
art that clamp support member 58 and drive shaft 30 may
alternatively be integrally formed as a single component. Clamp
support member 58 is unitarily constructed of a hardened steel or
other suitable material. Interconnection between clamp support
members 58 and drive shaft 30 is established through a roll pin 68
in interference fit engagement with a transversely extending
aperture 70 passing through clamp support member 58 and a
corresponding aperture 72 disposed in reciprocating drive shaft
30.
Clamp support member 58 includes a main body portion 73 which
partially defines a longitudinally extending channel 74 sized to
receive reciprocating drive shaft 30. More particularly, the
longitudinal channel 74 is defined by an inner wall 75 and by first
and second opposing side walls 76 and 78 which each terminate at
end walls 80 and 82, respectively. Inner wall 75 is concavely
curved to receive a second side wall 79 of reciprocating drive
shaft 30. In the first preferred embodiment, a first side wall 52
of reciprocating drive shaft 30 is adapted to sit flush with end
walls 80 and 82 (as shown in FIGS. 11 and 12). End walls 80 and 82
cooperate with first side wall 52 to provide a surface against
which saw blade 38 is disposed when operatively connected with a
power tool 10.
Adjacent an upper surface 86, clamp support member 58 is formed to
integrally include an L-shaped flange 88 which partially defines a
channel 90 for receiving an upper surface 94 of saw blade 38.
Adjacent a lower surface 96, clamp support member 58 includes an
outwardly extending portion 98 adapted to abut a lower surface 100
of saw blade 38. Upper surface 86 of clamp support member 58
includes a pair of spaced, upwardly extending flange portions 102
and 104. As will be appreciated below, flange portions 102 and 104
cooperate to limit longitudinal movement of biasing member 60. A
second transversely extending channel 108 is partially defined
between the main body portion 73 of clamp support member 58 and a
downwardly extending portion 110 of a rear wall 112 of clamp
support 58. Channel 108 is open along a bottom side.
Referring specifically to FIG. 6, the biasing member of the present
invention is preferably illustrated as a spring clamp member 60.
Spring clamp member 60 is adapted to be directly carried by clamp
support member 58 for movement with reciprocating drive shaft 30.
Spring clamp member 60 is generally C-shaped and is integrally
formed of a resilient metal or other suitable material to include a
curvilinear central portion 120 and first and second ends 122 and
124. In one application, spring clamp member 60 is constructed of
0.050 inch steel. A side view of clamp spring member 60 is shown in
FIG. 6 in a substantially unloaded condition. An aperture 125
passes through central portion 120 which is adapted to accept an
end of drive pin 42 when a saw blade is not in clamping arrangement
56.
Clamp spring member 60 further includes generally linear upper and
lower segments 126 and 128 integrally attached to opposite ends of
curvilinear central portion 120. Upper and lower segments 126 and
128 are disposed generally transverse to curvilinear central
portion 120 and cooperate with the curvilinear central portion 120
to partially define a longitudinally extending opening 130 for
receiving a portion of clamp support member 58 and reciprocal drive
shaft 30.
Spring clamp member 60 is further shown to include a retaining
portion 132 adjacent second end 124 which is adapted to be
constrained within longitudinal channel 108 of clamp support member
58. Spring clamp member 60 further integrally includes a spring tab
portion 136 adjacent first end 122 which extends upwardly relative
to upper segment 126 and is angled slightly rearwardly in the
direction of curvilinear central portion 120. Spring tab portion
136 is free from direct constraint with respect to clamp support
member 58.
When assembled and in clamping engagement with drive shaft 30 and
saw blade 38, lower segment 128 of spring clamp member 60 is
positioned adjacent bottom surface 96 of clamp support member 58.
In an unloaded condition, upper segment 126 of spring clamp member
60 is arranged to be positioned substantially adjacent upper
surface 86 of clamp support member 58. As discussed above,
longitudinal translation of spring clamp member 60 is limited by
flange portions 102 and 104 of clamp support member 58.
Curvilinear central portion 120 includes a lower, outwardly curved
segment 139 which accommodates saw blade 38 and an upper, outwardly
curved segment 140. Curvilinear central portion 120 further
includes an inwardly curved central portion 142 arranged to
directly contact saw blade 38. It will be appreciated by those
skilled in the art that the particular construction of spring clamp
60 is subject to modification without departing from the scope of
the present invention. Any construction will be suitable which
incorporates a portion for fixation to clamp support member 58, a
portion for directly biasing saw blade 38 and a displaceable free
end.
While in a clamping position such as that shown in FIG. 11, clamp
spring member 60 functions to exert a biasing force against saw
blade 38 through contact of central portion 142 and saw blade 38.
The biasing force serves to retain saw blade 38 in operative
connection with reciprocating drive shaft 30 by preventing saw
blade 38 from moving transversely with respect to drive shaft
30.
It will be appreciated by those skilled in the art that clamping
arrangement 56 of the present invention is able to accommodate saw
blades of various configurations without modification. By way of
example and not of limitation, two alternative saw blade
constructions suitable for use with clamping arrangement 56 are
illustrated in FIGS. 9 and 10. Referring to FIG. 9, a first
alternative saw blade 38' includes a generally rectangular mounting
portion 46' formed with an aperture 48' sized to receive drive pin
42. In FIG. 10, a second alternative saw blade 38'' is shown to
include an aperture 48'' and a longitudinally extending slot 144.
Any of a number of other known saw blade constructions may be
releasably interconnected to drive shaft 30 through clamping
arrangement 56 of the present invention.
As shown throughout the drawings, actuation member of the present
invention is preferably illustrated as a release lever 62 operative
to overcome the biasing force of spring clamp member 60 and thereby
facilitate removal and replacement of saw blade 38. In the
exemplary embodiment illustrated, release lever 62 is mounted for
pivotal movement between a first stable position or clamped
position (shown in FIG. 11) and a second stable position or
unclamped position (shown in FIG. 12). Significantly, when release
lever 62 is in its first stable position, it is spaced apart from
spring clamp member 60 permitting release lever 62 to remain
longitudinally fixed with respect to housing 18. Thus, release
lever 62 remains relatively stationary as reciprocating drive shaft
30 operates, thereby reducing the weight translated back and forth
by drive shaft 30 and also reducing attendant vibration forces.
To facilitate pivotal mounting of release lever 62, power tool 10
further includes an end plate 150 interconnected with first and
second forwardly extending sidewall members 32 and 34. As shown in
FIG. 2, end plate 150 is generally planar and has a configuration
similar to front face 24 of gear case housing 22. End plate 150
includes an aperture 152 through which saw blade 38 is permitted to
pass. In the embodiment illustrated, end plate 150 is attached to
first and second forwardly extending side wall members 32 and 34 by
a plurality of threaded fasteners 154 adapted to pass through four
apertures 156 provided in the end plate. Fasteners 154 are adapted
to engage threaded holes 158 located in boss portions 160 on each
of the forwardly extending side walls members 32 and 34. In the
embodiment illustrated, boss portions 160 are located along the
free ends of first and second forwardly extending side wall members
32 and 34. It will be appreciated by those skilled in the art that
end plate 150 can be alternatively attached to forwardly extending
side wall members 32 and 34 in any of a number of other well known
manners. In this regard, it is anticipated that end plate 150 could
alternatively be welded to forwardly extending side walls members
32 and 34.
Release lever 62 has a generally L-shaped cross section including a
first leg 170 and a second leg 172. The longitudinal length of
release lever 62 is sufficient to extend along the entire travel
path of spring clamp member 60 as drive shaft 30 is reciprocated. A
longitudinally extending aperture 174 passes through the length of
release lever 62 at the junction of first and second legs 170 and
172 and is adapted to receive a pivot pin 176. Pivot pin 176
includes a first end 178 adapted to engage an aperture 180 formed
in front face 24 and a second end 182 adapted to engage an aperture
184 located in end plate 150. Second end 182 is of a reduced
diameter so as to prevent forward translation of pin 176.
As shown in FIGS. 11 and 12, release lever 62 is formed to include
a recess or pocket 188 configured to accommodate a torsion spring
190. Torsion spring 190 functions to bias release lever 62 towards
its first stable position (as shown in FIG. 11) and includes a
central portion surrounding an adjacent portion of pivot pin 176.
Torsion spring 190 also includes a fixed end 194 in engagement with
a boss portion 196 of recess 188. Torsion spring 190 further
includes a free end 198 adapted to engage a stop pin 200 extending
from front face 24 of gear case housing 22. Stop pin extends into
recess 180 to avoid interference with release lever 62.
As shown most clearly in FIGS. 11 and 12, second forwardly
extending wall member 34 is generally S-shaped in cross section and
includes an upper segment 208 providing a stop surface 210 arranged
to support release lever 62. Upper segment 208 serves to prevent
further rotation of release lever 62 in a counterclockwise
direction as shown in FIGS. 11 and 12. First leg 170 of release
lever 62 transversely extends slightly beyond an upper vertical
segment 212 of second forwardly extending wall member 34 so that
the operator can grasp a free end 214 of first leg 170.
First forwardly extending side wall member 32 is generally L-shaped
in cross-section and is formed along the perimeter of a
corresponding portion of front face 24 of gear case housing 22. An
upper segment 216 of second forwardly extending side wall member 34
terminates at a stop surface 218 for engaging release lever 62 when
release lever 62 is rotated to its second stable position (as shown
in FIG. 12).
Second leg 172 of release lever 62 includes an engagement surface
222 adapted to contact spring tab portion 136 of spring clamp
member 60. As shown in FIG. 12, clockwise rotation of release lever
62 about a longitudinal pivot axis defined by pivot pin 176 results
in contact between engagement surface 216 of second leg 172 and
spring tab portion 136 of spring clamp member 60. The length of
second leg 172 is significantly less than the length of first leg
170, thereby providing a mechanical advantage for overcoming the
biasing force exerted by spring clamp member 60.
The pivot axis of release lever 62 defined by pivot pin 176 is
disposed relative to engagement surface 222 of second leg 172 so as
to provide an over-centered relationship therebetween. As a result,
as release lever 62 approaches its second stable position (as shown
in FIG. 12), the opposing biasing force of spring clamp member 60
urges release lever 62 against stop surface 218 of first forwardly
extending wall portion 32.
With particular reference to FIGS. 11 and 12, the operation of the
clamping arrangement 56 of the present invention heretofore
detailed will now be described. Beginning with saw blade 38
operatively connected to reciprocating drive shaft 30, release
lever 62 is rotated in a clockwise direction from its first stable
position (shown in FIG. 11) by manual urging of first leg 170 to
overcome the biasing force of torsion spring 190. Initial clockwise
rotation causes second leg 172 of release lever 62 to engage spring
tab portion 136 of spring clamp member 62.
Continued clockwise rotation of release lever 62 serves to
transversely displace spring tab portion 136 and to overcome the
biasing force of spring clamp member 62 by elastically deforming
spring clamp member 60. More specifically, elastic displacement of
spring tab portion 136 creates a gap 224 between curvilinear
central portion 120 of spring clamp member 60 and saw blade 38. As
release lever 62 approaches its second stable position, the
over-centered relation between engagement surface 222 of second leg
172 and the pivot axis defined by pivot pin 176 causes the biasing
force of spring clamp member 60 to further urge release lever 62 in
a clockwise direction against stop surface 218. At this point,
release lever 62 will stay in its second stable position until
urged in the direction of its first stable position. As a result,
both of the operator' hands are free for handling replacement of
saw blade 38 or other necessary tasks.
Saw blade 38 can now be removed from power tool 10 and a new blade
can be inserted into gap 224 between spring clamp member 60 and
reciprocating drive shaft 30. Upper edge 94 of saw blade 38 is
located in channel 90 and aperture 48 is positioned over drive pin
42. Operating interconnection between saw blade 38 and
reciprocating drive shaft 30 is established by manual urging of
release lever 62 in a counterclockwise direction. Following initial
counterclockwise movement of lever 62, the biasing force of spring
clamp member 60 urges release lever 62 to its first stable
position.
Turning now to FIGS. 13-19 of the drawings, a saw blade clamping
arrangement 56' constructed in accordance with the second preferred
embodiment of the present invention will now be described. In this
second embodiment, components similar to those identified with
respect to the first embodiment will be designated in the drawings
with corresponding reference numerals. As with the first preferred
embodiment, saw blade clamping arrangement 56' is operative for use
with power tool 10 such as a reciprocating saw or other tool
including a reciprocating drive shaft 30.
As with the first preferred embodiment of the present invention,
the saw blade clamping arrangement 56' of the second preferred
embodiment includes a clamp support member 58, a biasing member 60
and an actuation member 62. The saw blade clamping arrangement 56'
of the second preferred embodiment departs from the first preferred
embodiment in that it additionally incorporates a locking member
230 operative to selectively engage saw blade 38 and interconnect
saw blade 38 to drive shaft 30. The remainder of this detailed
description of the second preferred embodiment will address
departures in construction and function of the second preferred
embodiment from the first preferred embodiment.
As shown in FIG. 13, drive shaft 30 of the second preferred
embodiment is generally cylindrical and includes an open distal end
232 for receiving a first end 234 of clamp support member 58. In
the exemplary embodiment illustrated, first end 234 of clamp
support member 58 and drive shaft 30 are interconnected by pin 68
which engages cooperating apertures 235 located in first end 234
and shaft 30. However, it will be appreciated by those skilled in
the art that any suitable manner may be utilized to operatively
interconnect clamp support member 58 with drive shaft 30. For
example, clamp support member 58 and shaft 30 may alternatively be
press fit together and brazed.
With reference to FIGS. 14 and 15, clamp support member 58 is shown
to include a generally rectangular channel 236 partially extending
longitudinally therethrough. Rectangular channel 236 is open
adjacent a second end 238, or distal end, of clamp support member
58 and is configured to receive mounting portion 46 of saw blade
38. Clamp support member 58 further includes a transversely
extending recess 240 having a generally conical portion 242 and a
reduced diameter cylindrical portion 246. Reduced diameter
cylindrical portion 246 is arranged to align with aperture 48 in
mounting portion 46 of saw blade 38 upon insertion of saw blade 38
into channel 236. Conical portion 242 is partially defined by an
upwardly extending cylindrical flange 248. As will become apparent
below, recess 240 is configured to cooperatively receive locking
member 230.
With continued reference to FIG. 13 and additional reference to
FIG. 16, locking member 230 is shown to include a generally conical
portion 250 configured to cooperate with conical portion 242 of
recess 240. In a similar manner, locking member 230 includes a
generally cylindrical portion 252 adapted for insertion into
cylindrical portion 246 of recess 240. When locking member 230 is
seated into recess 240 of clamp support member 58, cylindrical
portion 252 intersects rectangular channel 236 and engages aperture
48 in mounting portion 46 of saw blade 38, thereby operatively
interconnecting saw blade 38 with clamp support member 58. Locking
member 230 is shown to further include a head 254 interconnected to
conical portion 250 through a reduced diameter portion 256.
With reference now to FIGS. 13 and 17, biasing member 60 of the
second preferred embodiment will now be described. As with the
first preferred embodiment, biasing member 60 of the second
preferred embodiment is a spring clamp member 60 adapted to be
directly carried by clamp support member 58 for movement with drive
shaft 30. Spring clamp member 60 includes a first end 122
displaceable by actuation member 62 and a second end 124
constrained with respect to clamp support member 58. Second end 124
is constrained within longitudinal channel 108 of clamp support
member 58. Spring clamp member 60 normally functions to bias
locking member 230 to a seated position within recess 240 of clamp
support member 58 and thereby operatively interconnect clamp
support member 58 and saw blade 38.
As most clearly shown in FIG. 17, spring clamp member 60 includes
an aperture 258 disposed adjacent first end 122. Aperture 258
includes an elongated portion 260 interconnected to a circular
portion 262. In use, head 250 of locking member 230 is inserted
through circular portion 262 of aperture 258 and reduced diameter
portion 256 of locking member 230 is positioned within elongated
portion 260. As first end 122 of spring clamp member 60 is
deflected by actuation member 62, reduced diameter portion 256 of
locking member 230 is permitted to translate within elongated
portion 260.
As with the first preferred embodiment, the release lever 62 of the
second preferred embodiment is pivotally interconnected to housing
18 for movement between a first position and a second position. In
this regard, pivot pin 176 passes through longitudinally extending
aperture 174. First end 182 engages aperture 184 formed in cover
plate 150. Similarly, second end 178 engages aperture 180.
In the first position (as shown in FIG. 19), release lever 62 is
spaced apart from spring clamp member 60 and does not reciprocate
with drive shaft 30. Free end 214 of release lever 62 abuts a lip
262 formed with housing 18 to prevent further rotation of release
lever 62 in a clockwise direction as shown in the drawings. In its
second position (as shown in FIG. 18), release lever 62 displaces
first end 122 of spring clamp member 60, thereby partially removing
locking member 230 from recess 240. As a result, cylindrical
portion 252 is withdrawn from channel 236 and aperture 48 of saw
blade 38, thereby permitting removal of saw blade 38.
Turning now to FIGS. 20-31 of the drawings, a saw blade clamping
arrangement 56'' constructed in accordance with the third preferred
embodiment of the present invention will now be described. Again,
components similar to those identified with respect to the first
embodiment will be designated in the drawings with corresponding
reference numerals. As with the first and second preferred
embodiments, saw blade clamping arrangement 56'' is operative for
use with power tool 10 such as reciprocating saw or other tool
including a reciprocating drive shaft 30.
As with the first preferred embodiment of the present invention,
saw blade clamping arrangement 56'' of the third preferred
embodiment includes a support member 58, a biasing member 60 and an
actuation member 62. Saw blade clamping arrangement 56'' of the
third preferred embodiment departs from the first preferred
embodiment in that it additionally incorporates a locking member
310 operatively interconnect saw blade 38 to drive shaft 30, a
control member 312 operative to displace locking member 310, and a
collar 314 movably supporting control member 312. The remainder of
this detailed description will address departures in construction
and function of the third preferred embodiment from the prior
embodiments.
As with the second preferred embodiment, drive shaft 30 of the
third preferred embodiment is generally cylindrical and includes an
open distal end 232 for receiving a first end 234 of support member
58. Preferably, first end 234 of support member 58 and shaft 30 are
press-fit together and brazed. Alternatively, it will be
appreciated by those skilled in the art that any suitable manner
may be utilized to operatively interconnect support member 58 with
drive shaft 30.
With specific reference to FIGS. 25 and 26, clamp support member 58
of tool 56 is shown to include a pair of spaced apart legs 316. A
generally rectangular channel 318 (best shown in FIG. 24) is
partially defined by the pair of legs 316 and extends substantially
the entire length of legs 316 and is adapted to receive mounting
portion 46 of saw blade 38. Support member 58 further includes a
transversely extending elongated hole 320. Aperture 320 extends
through a first leg 316a and intersects rectangular channel 318.
Upon insertion of saw blade 38 into channel 318, aperture 320 is
substantially aligned with aperture 48 in mounting portion 46 of
saw blade 38. As will become apparent immediately below, aperture
320 is configured to receive locking member 310. Locking member 310
of the third preferred embodiment is shown to preferably comprise a
spherical bearing 310. Bearing 310 has a diameter slightly smaller
than the width of elongated hole 320. The elongated configuration
of the hole allows the bearing 310 to float and easily locate hole
48 in saw blade 38.
With reference now to FIGS. 21, 22, 27 and 28, control member 312
of the third preferred embodiment will now be described. Control
member 312 is interconnected to support member 58 so as to be
linearly translatable with respect thereto. In the embodiment
illustrated, control member 312 is linearly translatable in a
direction substantially perpendicular to the direction of
reciprocal motion of drive shaft 30 between a first position and a
second position. As will be discussed further below, control member
312 is operatively retained relative to support member 58 through
collar 314. Control member 312 is operative for selectively urging
bearing 310 into engagement with saw blade 38 to thereby
operatively engage saw blade 38 with drive shaft 30. More
particularly, in a first position, as shown specifically in FIG.
21, control member 312 urges bearing 310 into engagement with saw
blade 38. In this first position, bearing 310 is partially inserted
into aperture 46 from a first side of saw blade 38. In its second
position, as shown in FIG. 22, control member 312 permits bearing
310 to be displaced from a position engaged with aperture 46 of saw
blade 38, thereby permitting removal and replacement of saw blade
38.
With continued reference to FIG. 27 and the cross-sectional view of
FIG. 28, control member 312 is shown to include a channel 326 for
at least partially receiving bearing 310. The channel 326 includes
a dish-shaped pocket 328 and a concavely curved trough 330. Trough
330 is defined by a camming surface which is angled such that
trough 330 is most shallow at a point displaced from cavity 328.
When control member 312 is in its second position (as shown in FIG.
22), locking member 310 is substantially centered within cavity 328
of channel 326. As a result, bearing 310 can be displaced from a
position in which it is engaged with aperture 46 of saw blade 38.
As control member 312 is moved from its second position to its
first position, bearing 310 rides along trough 330. Given the
angular orientation of trough 330, bearing 310 is resultantly
forced toward rectangular channel 318 and into engagement with
aperture 46 of saw blade 38.
With reference to FIGS. 29-31, collar 314 of the third preferred
embodiment of the present invention will now be described. As noted
above, collar 314 functions to interconnect control member 312 with
support member 58, and in turn drive shaft 30. Collar 314 includes
a main body portion 332 which defines a central aperture 334
adapted to receive the pair of legs 316 of the support member 58.
As a result, collar 314 effectively circumferentially surrounds
support member 58. A cotter pin 336 passes through a hole 338 in
main body portion 332 and a corresponding hole 340 in support
member 58 to thereby releasably interconnect 314 and support member
58.
As shown specifically in FIG. 30, collar 314 defines a generally
T-shaped channel 339 adapted to slidingly receive control member
312. More particular, T-shaped channel 339 includes a vertically
oriented portion 340 and a horizontally oriented portion 342.
Vertically oriented portion 340 is specifically adapted to receive
a pair of outwardly extending flanges 344 which are integrally
formed with control member 312. A flange 346 extends through
horizontally oriented portion 342 and slightly beyond.
It will be appreciated that in certain applications it may be
desirable to provide the collar 314 in two components. For example,
a two-component collar may provide manufacturing advantages. With
reference to FIGS. 32 and 33, an alternative two-piece collar 314
for use with the saw blade clamping arrangement 56'' of the third
preferred embodiment. The collar 314 is shown to include two
components, namely. An outer member 350 is shown in FIGS. 32A and
32B. An inner member 352 is shown in FIGS. 33A and 33B. The outer
and inner members 350 and 352 cooperate to accomplish the functions
on the collar 314 discussed above.
In the embodiment illustrated, biasing member 60 comprises a coil
spring 60 which circumferentially surrounds support member 58. As
shown in FIG. 23, a first end 350 of coil spring 60 engages an
aperture 352 formed in support member 58. A second end 354 of coil
spring 60 and aperture 356 formed in flange 346 below control
member 312. Coil spring 60 functions to normally bias control
member 312 towards its first position (as shown in FIG. 21) in
which bearing 310 is forced into engagement with aperture 46 of saw
blade 38.
Referring now to FIGS. 20-22, the release lever of the third
preferred embodiment is shown pivotally interconnected to housing
18 for movement between a first position (as shown in FIG. 21) and
a second position (as shown in FIG. 22). In this regard, a pivot
pin 176 passes through a longitudinally aperture in release lever
62. First end 182 of pivot pin 186 engages apertures 184 formed in
cover plate 150. Second end 178 of pivot pin 176 engages aperture
180. Alternatively, it will be appreciated by those skilled in the
art that release lever 62 can be integrally formed to include
cylindrical portions extending in opposite directions and
effectively replacing pivot pin 176.
In the first position, release lever 62 is spaced apart from flange
346 of control member 312. It will be appreciated that release
lever 62 does not reciprocate with drive shaft 30. In its second
position, release lever 62 displaces control member 312 to its
second position, thereby permitting removal and replacement of saw
blade 38 in the manner discussed above. In the preferred
embodiment, release lever 62 of the third preferred embodiment is
mounted to tool 10 such that an interference fit is established so
as to maintain release lever 62 in its release position.
Alternatively, release lever 62 may be mounted to tool 10 such that
its second position (as shown in FIG. 22) is an over-centered
position.
In the exemplary embodiment illustrated, the saw blade clamping
arrangement 56'' of the third preferred embodiment is shown to
include a locating pin 360 which extends into the longitudinal
opening of the support member 58 and is adapted to engage the
aperture 46 of the saw blade 38 from a second side of the saw blade
38. Spherical bearing 310 and locating pin 360 cooperate to prevent
inadvertent removal of saw blade 38 from the longitudinal slot. In
this regard, locating pin 360 prevents spherical bearing 310 from
being pushed out of aperture 46 when saw blade 38 is under severe
loads. Locating pin 360 is adapted to seat in aperture 46 of blade
38 and accordingly serves to further lock blade 38 in place. The
diameter of locating pin 360 is smaller than aperture 46 of saw
blade 38, thereby permitting spherical bearing 310 and the spring
force applied to spherical bearing 310 to locate blade 38 within
clamp support member 58. Specifically, to prevent release of blade
38 from clamp support member 58 when spherical bearing 310 tends to
slide out of the longitudinal blade opening slot, the sidewall of
aperture 46 of saw blade 38 engages locating pin 360 and blade 38
is retained within clamp support member 58.
Turning now to FIGS. 35-40 of the drawings, a saw blade clamping
arrangement 56''' constructed in accordance with the teachings of
the fourth preferred embodiment of the present invention will now
be described. The saw blade clamping arrangement 56''' of the
fourth preferred embodiment will be understood to be substantially
identical to the saw blade clamping arrangement 56'' of the third
preferred embodiment except that the clamping arrangement 56''' of
the fourth preferred embodiment has been modified to include a
mechanism 400 for ejecting the saw blade 38 therefrom. Components
similar to those identified with regard to previously described
embodiments will be designated in the drawings with corresponding
reference numerals.
The ejection mechanism 400 of the fourth preferred embodiment of
the present invention is illustrated to generally include a plunger
402, an end cap 404, and a coil spring 406. As with the prior
embodiments, the clamping arrangement 56''' includes a mounting
member or clamp support member 408. The clamp support member 408 is
similar in function and construction to the clamp support member 58
with the exception that it has been modified to accommodate the
plunger 402. In this regard, the clamp support member 408, which is
press-fit into an end of the drive shaft 30, defines a generally
cylindrical cavity 410. The cylindrical cavity 410 is shown most
clearly in the cross-sectional view of FIG. 37.
The plunger is an elongated plunger 402 including a first end 412
and a second end 414. A radially extending flange 416 is disposed
between the first and second ends 412 and 414. The plunger 402 is
disposed within the cavity 410, with the first end 412 extending
through a reduced diameter aperture 418 provided in the clamp
support member 408. The second end 414 extends from an aperture 420
provided in the cap 404 which is press-fit into a countersunk
portion 422 of cavity 410. The cap 404 is shown to include an
axially extending flange 424.
The plunger 402 is linearly movable between a first position (shown
in FIG. 36) and a second position (shown in FIG. 35) for ejection
the saw blade 38 from the saw blade clamping arrangement 56'''. In
the exemplary embodiment, the saw blade clamping arrangement 56'''
includes a biasing member in the form of a coil spring 426 which
surrounds the second end 414 of the elongated plunger 402 and
biases the plunger 402 to the second position. The coil spring 426
is opposed on one side the cap 404 and on the other side by the
flange 416.
When the saw blade 38 is inserted into the saw blade clamping
arrangement 56''', the saw blade 38 abuts the first end 412 of the
plunger 402 and displaces the plunger 402 rearwardly. This rearward
translation of the plunger 402 compresses the coil spring 426
between the cap 404 and the flange 416. When removal or replacement
of the saw blade 38 is desired, the release lever 62 is operated to
move the saw blade clamping arrangement 56''' to its unclamped
position and the biasing force of the coil spring 426 forces the
plunger 402 to its second position to thereby eject the saw blade
38.
Turning now to FIGS. 41-50 of the drawings, a saw blade clamping
arrangement constructed in accordance with the teachings of a fifth
preferred embodiment of the present invention is illustrated and
generally identified at reference character 500. As with the prior
embodiment of the present invention, the saw blade clamping
arrangement 500 is operative to releasably couple a saw blade 38
with a reciprocating drive shaft 30 of a power tool 10 such as
reciprocating saw. Primarily, the saw blade clamping arrangement
500 of the fifth preferred embodiment of the present invention
functionally differs from the remaining embodiments described
herein by being able to accommodate the saw blade 38 in various
orientations. As will be more appreciated below, this aspect of the
present invention provides the user of the tool 10 with improved
flexibility to avoid obstacles that may be encountered during
cutting operations.
Prior to addressing the specific construction and operation of the
clamping arrangement 500, a brief understanding of the various saw
blade orientations is warranted. FIG. 41 illustrates a first
cutting position in which the blade 38 is disposed in a generally
vertical plane and the teeth of the blade 38 are oriented downward.
This blade orientation is typical of known reciprocating saws. FIG.
42 illustrates a second cutting position in which the blade 38 is
again oriented in a generally vertical plane. In this second
cutting position, the teeth of the blade 38 are oriented upward.
FIG. 43 illustrates a third cutting position in which the blade 38
is oriented in a generally horizontal plane and thereby mutually
perpendicular to the first and second cutting positions. FIG. 44
illustrates a fourth cutting position in which the blade 38 is
again oriented in a generally horizontal plane. In this fourth
cutting position, the teeth of the blade 38 are oriented in a
direction opposite to the third cutting position of FIG. 43.
The clamping arrangement 500 is illustrated to generally include a
clamp base or clamp support 502 and a control member or slider 504.
The clamp base 502 includes a mounting portion 506 defining an
aperture 508. In the preferred embodiment, the aperture 508
receives a fastener 509 (shown in FIG. 43B) for removably attaching
the clamp base 502 to the reciprocating shaft 30 of the tool 10.
Alternatively, the clamp base 502 may be press fit or otherwise
suitable attached to the shaft 30.
The clamp base 502 defines a first or vertical slot 510 for
receiving the blade 38 in either the first cutting position (as
shown in FIG. 41) or the second cutting position (as shown in FIG.
42). As shown in connection with the prior embodiments of the
present invention, the saw blade 38 includes a mounting portion 46
including an aperture 48. As perhaps shown most particularly in the
cross-sectional views of FIGS. 47 and 48, the clamp base 502
defines an aperture or opening 512 that intersects the first slot
510 and is configured to receive a locking member or ball 514. In a
manner to be addressed more specifically below, the locking ball
514 engages the aperture 46 of the saw blade 38 for securing the
saw blade 38.
The clamp base further defines a hole 516. The hole 516 receives a
locating pin 518 (see FIG. 47). The locating pin 518 extends into
the opening 510 and cooperates with locking ball 514 to prevent
inadvertent removal of the saw blade 38 from the slot 510. The
locating pin 516 is adapted to seat in the aperture 46 of the blade
38 and accordingly serves to further lock the blade 38 in place. In
this regard, the locating pin 518 prevents the locking ball 514
from being pushed out of the aperture 46 when the saw blade 38 is
under severe loads.
The clamp base 502 is further illustrated to include a second or
horizontal slot 520. The second slot 520 is operative to receive
the saw blade 38 in the third cutting position (shown in FIG. 43)
or the fourth cutting position (shown in FIG. 44). Significantly,
the second slot 520 is spaced from the first slot 510. In this
manner, the saw blade 38 is off center relative to the drive shaft
30 and positioned proximate a side wall of the tool housing. Such
positioning of the saw blade 38 closer to the side wall of the tool
housing facilitates flush cutting of a work piece with the saw
blade 38.
The second slot 520 is intersected by a third slot 522 that
slidably receives the slider 504. The slider or control member 504
is linearly translatable within the third slot in a direction
substantially perpendicular to the direction of reciprocal motion
of the driveshaft 30 between a first position and a second
position. As will be explained further below, the slider 504 is
operative for selectively urging the locking ball 514 into
engagement with the saw blade 38 to thereby operatively engage the
saw blade 38 with the drive shaft 30. In the first position, as
shown specifically in the cross-sectional view of FIG. 47, the
slider 504 urges the locking ball 514 into engagement with the saw
blade 38. In this first position, the locking ball 514 is partially
inserted into the aperture 46 from the first side of the saw blade
38. In its second position, as shown in the cross-sectional view of
FIG. 48, the slider 504 is linearly translated downward and permits
the locking ball 514 to be displaced from a position engaged with
the aperture 46 of the saw blade 38. In this manner, removal and
replacement of the saw blade 38 is permitted.
The slider 504 includes a first portion for selectively creating an
operative connection between the saw blade 38 and the reciprocating
drive shaft 30. In the embodiment illustrated, the first portion
comprises a channel or camming slot 524 for at least partially
receiving the locking ball 514. The channel 524 comprises a
concavely curved trough defined by a camming surface which is
angled such that the downward displacement of the slider 504 from
the first position to the second position provides additional
clearance for the locking ball 514 to accommodate movement away
from the saw blade 38. Given the angular orientation of the channel
524, as the control member 504 is moved from its second position to
its first position, the locking ball 514 is resultantly forced into
the aperture 512 and toward the saw blade 38.
The slider 504 will be understood to be further operative to
selectively retain the saw blade 38 relative to the drive shaft 30
when the saw blade 38 is in its third cutting position or fourth
cutting position. In this regard, the slider 504 further includes a
second portion 530 for selectively creating an operative connection
between the saw blade 38 and the reciprocating drive shaft 30 when
the saw blade 38 is in its third cutting position or fourth cutting
position. In the embodiment illustrated, the second portion is an
integrally formed pin 530. As perhaps shown most particularly in
the cross-sectional view of FIG. 49, when the slider 504 is
translated upward to its first position, the integrally formed pin
530 of the slider 504 engages an aperture of the saw blade 38. In
this manner, the saw blade 38 is retained within the slot 520.
Conversely, translation of the slider 504 from its first position
downward to its second position, displaces the pin 530 from the saw
blade 38 to permit removal and/or replacement of the saw blade
38.
As with the prior embodiments, the clamping arrangement 500
includes a release lever 532 which functions to translate the
slider 504 from the first position to the second position. In a
normal position (as shown in FIG. 41), the release lever 532 is
spaced apart from a flange 536 of the slider 504. It will be
appreciated that the release lever 532 does not reciprocate with
the drive shaft 30 of the tool 10. The release lever 532 is movable
(i.e., rotatable) to a second position (as shown in FIG. 48). In
this second position, the release lever 130 displaces the slider
504 downward to its second position and thereby permits removal and
replacement of the saw blade 38 in the manner discussed above. The
slider 504 is biased upward (as shown in FIGS. 47 and 49) to its
first position by a biasing member 538 (shown in FIG. 43B). The
biasing member 538 is preferably a spring 538. A spring identical
in construction and function is shown in FIG. 23 in connection with
the third embodiment of the present invention and need not be
described in connection with this embodiment.
It will now be understood that the present invention provides the
user of the tool 10 with improved flexibility to avoid obstacles
that may be encountered by the handle, motor, or other parts of the
tool 10 during cutting operations. In this regard, the saw blade 38
can be oriented in various ways relative to the geometry of the
remainder of the tool 10 to minimize difficulties encountered with
obstacles. One example of this aspect of the present invention is
shown particularly in FIGS. 43A, 43B and 50. In FIG. 43B, the saw
blade 38 is received by the clamp support 502 in the third
orientation. The saw blade 38 is displaced from a longitudinal axis
of the drive shaft 30. As a result, the saw blade 38 is positioned
closer to a side wall of a housing of the tool 10 (see FIG. 43A).
In FIG. 50, the tool 10 is being used with the blade 38 in this
third orientation to flush-cut a work piece adjacent a wall portion
or planar member. A more flush cut of the work piece is facilitated
in this manner.
While the above description constitutes various preferred
embodiments of the invention, it will be appreciated that the
invention is susceptible to modification, variation, and change
without departing from the proper scope or fair meaning of the
accompanying claims. For example, it will be understood that the
teachings of the present invention are directly applicable to other
power tools having reciprocating drive shafts, including but not
limited to jigsaws.
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